//除自身以为数组的乘积

class Solution {
public:
    vector<int> productExceptSelf(vector<int>& nums) {
        int n = nums.size();
        vector<int> f(n);
        vector<int> g(n);
        f[0] = 1;
        g[n - 1] = 1;
        for(int i = 1; i< n; i++)
        {
            f[i] = f[i - 1] * nums[i - 1];
        }
        for(int j = n - 2; j >= 0; j--)
        {
            g[j] = g[j + 1] * nums[j + 1];
        }
        vector<int> ret(n);
        for(int i = 0; i < n; i++)
        {
            ret[i] = f[i] * g[i];
        }
        return ret;
    }
};